c - Error in inserting nodes in red black trees -

i trying insert nodes in red black trees. functions rotate_left, rotate_right, insertion correct rb_fixup seems wrong. red color shown 1 , black 0. have implemented algo clrs. when third element inserted gives segmentation fault. code of rb_fixup is:

struct node {     int data;      int color;     struct node *left;     struct node *right;     struct node *parent; }*root;   rb_fixup(struct node *z) {      struct node *y;     y=(struct node *)malloc(sizeof(struct node));     while(z->parent->color==1)     {         if(z->parent==z->parent->parent->left)         {             y=z->parent->parent->right;             if(y->color==1)             {                 z->parent->color=0;                 y->color=0;                 z->parent->parent->color=1;                 z=z->parent->parent;             }             else if(z==z->parent->right)             {                 z=z->parent;                 rotate_left(z);             }             z->parent->color=0;             z->parent->parent->color=1;             rotate_right(z->parent->parent);          }         else if(z->parent==z->parent->parent->right)         {             y=z->parent->parent->left;             if(y->color==1)             {                 z->parent->color=0;                 y->color=0;                 z->parent->parent->color=1;                 z=z->parent->parent;             }             else if(z->parent->left==z)             {                 z=z->parent;                 rotate_right(z);             }             z->parent->color=0;             z->parent->parent->color=1;             rotate_left(z->parent->parent);         }     }     root->color=0; } 

i solved above problem. error above code if uncle red, color uncle , parent black , grandparent red goes down operations written after else if of each condition , many conditions not done correctly. final code looks following:-

rb_fixup(struct node *z) {      struct node *y;     y=(struct node *)malloc(sizeof(struct node));     while(z->parent->color==1 && z->parent!=null)     {         if(z->parent==z->parent->parent->left)         {             if(z->parent->parent->right!=null)             y=z->parent->parent->right;             if(y->color==1)             {                 z->parent->color=0;                 y->color=0;                 z->parent->parent->color=1;                 z=z->parent->parent;             }             else if(z==z->parent->right)             {                 z=z->parent;                 rotate_left(z,z->right);                 z->parent->color=0;                 z->parent->parent->color=1;                 rotate_right(z->parent->parent,z->parent);             }             else             {                 z->parent->color=0;                 z->parent->parent->color=1;                 rotate_right(z->parent->parent,z->parent);             }         }         else          {             if(z->parent->parent->left!=null)             {                 y=z->parent->parent->left;             }                        if(y->color==1)             {                 z->parent->color=0;                 y->color=0;                 z->parent->parent->color=1;                 z=z->parent->parent;                             }             else if(z==z->parent->left)             {                 z=z->parent;                 rotate_right(z,z->left);                 z->parent->color=0;                 z->parent->parent->color=1;                 rotate_left(z->parent->parent,z->parent);             }             else             {                 z->parent->color=0;                 z->parent->parent->color=1;                 rotate_left(z->parent->parent,z->parent);             }         }     }     root->color=0; }